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Renal cell carcinoma
Renal cell carcinoma (RCC) is the most common form of primary kidney cancer '''(PKC), accounting for about 90-95% of all PKCs and 2-3% of cancer cases overall. It usually develops in those between the ages of '''50 and 70 years, especially in smokers, the obese, those with high blood pressure and the risk seems to be influenced by genetics, exposure to toxic chemicals and certain medications. It is about 50-100% more frequent in males than in females and is associated with about twice as many deaths in men than in women. Currently the only hope at a cure is surgical removal of the tumour, which is only possible during the early stages of the disease. Complete surgical removal of the tumour is only possible in earlier stages of the disease, although often surgery is attempted even in more advanced cases so as to relieve the symptoms and give the affected person some more time. This is because of the fact that all other treatments merely serve to slow the cancer's progression and not to cure it. RCC is special amongst cancers in that it does not tend to respond to either chemotherapy or radiotherapy and is associated with amongst the highest rates of associated paraneoplastic syndromes. Until fairly recently (late 1990s onwards is 'fairly recent') the only effective therapy was surgery, with all other treatments being purely palliative (like hydromorphone, morphine and/or oxycodone for pain). Nowadays the 5-year survival rate is about 72% for Australians with RCC. Some 2,000, 10,000 and 64,000 new cases of kidney cancers are estimated to be diagnosed every year in Australia, the U.K. and the U.S.A., respectively. Classification There are five major subtypes of RCC: clear-cell (accounts for 60-75% of cases, overall), papillary (5-15%), chromophobic (5-10%), oncocytoma (3-10%) and Bellini/collecting duct (<1%). Clear-cell and papillary tumours affect the proximal tubule, chromophobic and oncocytic subtypes originate from the cortical collecting duct 'and are fairly benign in their clinical course as for the ''Bellini duct subtype it is a very aggressive subtype and arises from the '''medullary (or Bellini) collecting duct. Staging Generally RCC is classified style https://en.wikipedia.org/wiki/TNM_staging_system, although prognostic group staging is also sometimes used: where T1 with N0 and M0 is equivalent to stage I, T2 with N0 and M0 is stage II, T3 with N0/N1 and M0 or T1/T2 with N1 and M0 is stage III and T4 (with any N or M) or any T with any N and M1 is stage IV. Signs and symptoms Signs and symptoms include (with their frequency in brackets): * Haematuria (40%) * Flank pain (40%) * Weight loss (33%) * Mass in the abdomen (25%) * Fever (20%) *Hypertension (20%) * Signs of hypercalcaemia (5%), such as nausea, vomiting, altered mental status, abdominal pain, constipation, lethargy, depression, etc. * Night sweats * Malaise, lethargy, and other signs of anaemia * One-sided (usually left-sided) scrotal swelling in males Causes The exact cause if unknown but a number of risk factors are known. These risk factors can be divided into four major categories: exposures, lifestyle factors, medical factors and genetics. Genetic factors, including various genetic disorders such as von Hippel-Lindau syndrome, hereditary papillary renal carcinoma, Birt-Hogg-Dube syndrome, hereditary renal carcinoma and tuberous sclerosis, are known to be responsible for some cases. Chemical exposures known to contribute to RCC risk include: benzene, benzidine, cadmium, herbicides, trichloroethylene and vinyl chloride. Lifestyle factors that are known to contribute to RCC risk include: obesity (an especially powerful risk factor in females) and smoking (which contributes to one-third of all cases, an doubles one's risk of RCC). Medical factors include long-term dialysis treatment, hypertension and the use of non-aspirin non-steroidal anti-inflammatory drugs (on average this increases risk by ~50%) /phenacetin (a prodrug to paracetamol that has been withdrawn from the international market due to its effects on the kidneys). Mechanism RCCs most often arise from the proximal convoluted tubules of the kidney's nephrons. The malignant cells often have chromosomal abnormalities in chromosome 3 (specifically its short arm) (in both inherited and non-inherited cases). Diagnosis The diagnosis of RCC is usually made via imaging studies (like with , , and assorted other scans), blood tests, urine tests and a few other laboratory tests, although a biopsy is the only definitive test. Treatment The current mainstay of treatment, despite recent advances in drug therapies, is surgery, which currently offers patients' only hope for a cure despite the small yet always existent possibility of a spontaneous remission. It is highly resistant to chemotherapy and radiation, although it often sensitive to targeted therapies and immunotherapies. Surgery The most commonly-used and well-researched surgical treatment for RCC is a radical nephrectomy in which the entirety of the affected kidney and its associated lymphoid tissues and adrenal glands are removed. In cases of T1 tumours generally a partial nephrectomy is recommended as the first-line treatment if possible, so as to preserve as much kidney function as possible. In select circumstances laproscopic surgery may be attempted, most commonly in cases where the patient has only a single kidney, hence performing a radical nephrectomy would leave them with no residual kidney function. Targeted therapy Targeted therapies include tyrosine kinase inhibitors like axitinib, pazopanib, sorafenib and sunitinib, monoclonal antibodies like bevacizumab and mammalian target of rapamycin (mTOR) inhibitors like everolimus and temsirolimus. For tyrosine kinase inhibitors the major dose-limiting side effects are diarrhoea, hypertension, dermatologic side effects (e.g., rash and hand-foot syndrome), fatigue, elevated lipase (a pancreatic enzyme), lymphopenia and neutropenia. External links Notes Reference list Category:Cancer Category:Kidneys